<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>box</title>
    <style>
        .box {
            width: 500px;
            height: 300px;
            /*border: 1px solid black;*/
            /*padding: 10px;*/
            /*padding: 10px 20px 30px 40px;  !*方向为上右下左*!*/
            /*padding: 10px 20px;    !*上下为10px，左右为20px*!*/
            padding-top: 10px;
            padding-bottom: 10px;
            padding-left: 20px;
            padding-right: 20px;
            border-left: 2px solid black;
            border-bottom: 2px dashed green;
            border-right: 2px dotted purple;
            /*margin: 50px;*/
            margin: 10px auto;   /*左右外边距设置为自动，则居中显示*/
        }
        span {
            display: block;
            width: 200px;
            height: 50px;
        }
    </style>
</head>
<body>
<div>
    <span>Hello World!</span><span>How are you?</span>
</div>
<div class="box">
    达内云计算 Cloud Computing
</div>
</body>
</html>